| 摘要 |
The present invention is directed to the production of molded polyurethane products having high flexural moduli (i.e. 1,000,000 psi or more) and high elongation wherein a reaction mixture is reacted in a closed mold. The reaction mixture comprises reacting a liquid, room temperature stable, isocyanate prepolymer with at least two hydroxy-functional polyethers having average hydroxyl functionalities of from 1.5 to 8 and number average molecular weights of from 350 to 1800, at least one hydroxyl functional organic material containing from 2 to 8 hydroxyl groups and having a number average molecular weight below 350 and at least two hydroxyl functional organic materials having average hydroxy functionalities of from 1.5 to 3 and having number average molecular weights of 4000 or more. The products are prepared from these processes using such specified isocyanate prepolymers and polyol blends.
|
